Here is a one liner to check the database size for exchange databases.
Start Exchange management shell. Then run the following command:
Get-MailboxDatabase | foreach-object {add-member -inputobject $_ -membertype noteproperty -name mailboxdbsizeinGB -value ([math]::Round(([int64](get-wmiobject cim_datafile -computername $_.server -filter (‘name=”’ + $_.edbfilepath.pathname.replace(“\”,”\\”) + ””)).filesize / 1GB),2)) -passthru} | Sort-Object mailboxdbsizeinGB -Descending | format-table identity,mailboxdbsizeinGB
Source:
http://blogs.technet.com/b/gary/archive/2009/08/11/get-exchange-mailbox-database-size-one-liner-version-2.aspx
